Skip to content
DilutionScan

Trading halt

A trading halt is a temporary stop in trading of a security ordered by its listing exchange or the SEC, for example pending material news, to request information, or after a volatility pause.

Last verified

Types of halts

Halts are identified by codes published on exchange halt feeds. Common ones on Nasdaq include:

CodeMeaning
T1Halt, news pending
T2Halt, news released
T12Halt, additional information requested by the exchange
LUDPVolatility trading pause under the Limit Up-Limit Down Plan
H10SEC trading suspension

A news halt gives the market time to absorb material information, such as a merger announcement or trial result. A regulatory halt for additional information (T12) means the exchange has questions about the company, its disclosures or unusual trading, and it can last days or longer. A volatility pause under LULD is short and mechanical, normally five minutes. An SEC trading suspension can last up to 10 trading days.

How trading resumes

Exchanges announce a resumption time, and Nasdaq reopens halted securities with a halt cross, an auction that sets the reopening price from accumulated orders. A security halted for a long time may resume with a very different price.

Worked example

Hypothetical: Company X is halted T1 at 10:02 ET pending news. It publishes a press release at 10:15, the code changes to T2, and quoting resumes at 10:25 with trading at 10:30. Separately, Company Y moves outside its price band twice in a morning and is paused under LULD for five minutes each time.

Why it matters

During a halt, orders on the exchange cannot execute, and positions cannot be exited. A long regulatory halt can precede further action, such as a delisting determination. Halts around a reverse split effective date also occur at some venues.

How to spot it

The Signal8 halts screener shows current halts and codes; Nasdaq publishes the consolidated halt list on its trader site. See Trading halts.

Guides that use this term

Check any ticker for dilution

DilutionScan reads each covered company's SEC filings and lists its warrants, convertibles, ATM programs, shelves and S-1s on one page, with a dilution rating and cash runway.

Definition from the Signal8 Academy glossary. Educational content only. DilutionScan and Signal8 are not broker-dealers or investment advisers, and nothing here is a recommendation to buy or sell any security.

DilutionScan ProEvery instrument in full · $59/mo